I developed a simple Bitcoin Tool extension, that recognizes Bitcoin addresses on every website, and does some useful things with them:* Links addresses to blockexplorer.com, something for curious people, who want to examine quickly BTC sent, received, and the number of transactions* Adds a select button, that helps when you want to copy-paste the address, making sure no letter is omitted* Adds a Falkvinge button, that does not work, but why? Security reasons, Mr Falkvinge.

Update. The "Send BTC" button now works.It needs two applications running on your computer: bitcoind from the standard bitcoin client package, and a new program bitcoin_httpd which is an HTTP mini-server that displays a simple website and passes requests to bitcoind.Download the Linux version of bitcoin_httpd from here (md5 sum: 18fea1ef3eb16260b59bdb383c3a8812).The source code is here if you need it. It would be useful to compile it on Windows and Mac.

The link "download pdf" leads to BitcoinService, where the pdf file can be bought for 0.02 BTC.Bitcoin Tool changes the displayed plain text bitcoin address into a link and two buttons.

Clicking the Send BTC button opens in a new tab a local website served by bitcoin_httpd:

I fill the the form with the price 0.02, and with the proper RPC username and password from my bitcoin.conf file, and click "Send bitcoins".In my version 0.3.21 of bitcoind the fee of 0.01 BTC is applied, which sucks a bit for microtransactions like this one.

Response after clicking "Send bitcoins" shows that the transaction went all right.

I close the tab with the response, refresh the bitcoinservice website and finally I can enjoy the downloaded Bitcoin Sun pdf.